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When Extinct Isn’tQUESTIONING THE TERM AFTER A BIRD’S RETURN BY MARGUERITE HOLLOWAY

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The video images may be tiny, grainy, dark and fl eeting, but many looking at them see something glorious: evidence

that at least one ivory-billed woodpecker—

an 18- to 20-inch-tall bird with a wingspan of some 30 inches, last seen in the U.S. in 1944—is alive in the bottomland forest of eastern Arkansas. After a year of traipsing and canoeing through the Big Woods and its bayous, many inconclusive recordings of ivory-bill-like calls, seven good sightings and one fortuitous videotaping, scientists and conservationists announced in April that the bird was not extinct after all.

If the discovery holds up, the ivory-billed woodpecker will not be the only U.S. species recently returned from oblivion. In May, just a few days after the ivory-bill news, the Na-ture Conservancy announced the discovery in Alabama of three snails listed as extinct.

A few weeks later, botanists at the Univer-sity of California at Berkeley reported fi nd-ing the Mount Diablo buckwheat, a tiny pink-fl owered plant that had not been seen since 1936. At least 24 species of other pre-sumed or possibly extinct plants, insects and other organisms have been found during natural heritage surveys in North America since 1974, according to Mark Schaefer, president of NatureServe, a nonprofi t con-servation group based in Arlington, Va. There are examples from elsewhere as well. The Bavarian pine vole, last seen in 1962, scurried back into view in 2000. The New Zealand storm petrel and the Lord Howe Island stick insect are among the other spe-cies no longer missing.

With so many “extinct” creatures reap-pearing, it is reasonable to wonder if the word has lost its meaning—something Ross

2005 American Journal of Neuroradiology. “We can push the time window for tPA to eight hours.” Selecting patients for treat-ment on the basis of a “tissue clock” rather than the “ticking clock” gives many more patients a chance for a fuller recovery. As important, MRI and CT imaging may also identify those at risk for bleeding if given thrombolytics, a concern that keeps some physicians from administering tPA even within three hours.

Simple, nondrug measures may keep en-dangered neurons alive until they can be res-cued with tPA, says Aneesh B. Singhal of Massachusetts General Hospital, where a small pilot study gave participants high-fl ow oxygen through a face mask. “It buys time,” explains Singhal, who co-authored the pa-per on it in the April 2005 Stroke. “We can delay the progression of ischemic stroke by several hours. Because oxygen therapy is readily available in ambulances and the ER, it could make logical combination therapy” with tPA.

Meanwhile potentially safer drugs have entered late-stage clinical testing. Des-

moteplase, which derives from the saliva of a vampire bat, chews up the fi brin holding a clot in place just as tPA does, but it is more potent and selective. “Even at nine hours, patients had signifi cant long-term clinical benefi ts, in terms of better recovery after 90 days,” says Warach of phase II results. The drug recently entered phase III trials.

Another drug in phase III testing protects neurons by way of a different method. Cerovive (NXY-059) works by scavenging up free radicals that break down the blood-brain barrier and worsen stroke outcome. Preliminary results from a global trial, known as SAINT I, suggest the chemical reduces the amount of disability after a stroke.

Even with the good news, many patients will not qualify for these therapies, because they may still arrive too late or have contra-indications. A therapy that encourages brain cells to step up their own repair mechanisms might be the best solution, but that is still a long way off.

Cathryn M. Delude is a freelance writer based in Andover, Mass.

During an ischemic attack, the lack of oxygen endangers neurons, but

the treatment itself—the drug tPA—is toxic to stroke-stressed

blood vessels and neurons, according to Berislav Zlokovic of

the University of Rochester Medical Center. “We show that tPA breaches

the blood-brain barrier and kills neurons directly,” Zlokovic says of

his team’s report last year. The group discovered that activated

protein C (APC), a well-known drug used to treat sepsis, can override

tPA’s toxic effect in mice. As a stand-alone therapy, APC might

save neurons that would otherwise die. In combination with tPA, it

could increase tPA’s effectiveness after three hours by reducing

collateral damage.

NEED TO KNOW: TOXIC tPA

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SCANnews

Cosmic CAT ScanOBSERVING THE EARLY UNIVERSE—WITH 10,000 TV ANTENNAS BY W. WAY T GIBBS

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In the beginning, the universe was a void full of energy but without form. And so it remained for many millions of years—

exactly how long is still a major mystery of cosmology—until the fi rst stars condensed from the fog of matter and lit up with a blue nuclear glow.

Telescopes are just like time machines: the farther out in space they look, the fur-ther back into the past they peer. But even the best optical telescopes cannot make out what the universe was like at an age of less than one billion years. Before that time, a haze of neutral hydrogen gas shrouded

MacPhee, curator of mammalogy at the American Museum of Natural History, has been outspoken about. He worries that complacency may set in (if it hasn’t already), because many species that people read or hear about are described as either on the verge of extinction, already extinct or for-merly extinct. He cites the example of Miss Waldron’s red colobus monkey, extinct in 2000, alive in 2004. “The average person has been barraged with the same story over and over again,” he says. “People are using the term indiscriminately.”

To counteract this trend, MacPhee and his colleagues formed the Committee on Re-cently Extinct Organisms in the late 1990s, devising criteria to determine extinction reli-ably—including rigorous taxonomic identi-fi cation and a 50-year waiting period before declaring something extinct, an idea fi rst put forth by the Convention on International Trade in Endangered Species.

Schaefer and John W. Fitzpatrick of Cornell University, lead author of the ivory-billed woodpecker report, agree that “ex-tinction” should be applied more carefully. “The word ‘extinct’ is an absolute term, like pregnant or dead,” Fitzpatrick remarks, “so we need to describe the probability of that being true.” In cases such as the passenger pigeon, which has not been seen by anybody for nearly a century, “we treat it as formally extinct,” he notes. For many plants and small vertebrates, “we suspect extinction, but they may still be hiding in some spots. That was the case for the ivory bill.” Schae-fer says that his organization has a letter scheme to describe species as GX (presumed

extinct) or GH (possibly extinct) and then uses several other classifi cations, such as G1 (critically imperiled)—ranks also used by various federal agencies.

For now, the ivory-billed woodpecker seems to have been successfully upgraded. But “speaking probabilistically, this bird has a very, very slim chance of persisting,” Fitz-patrick points out. “The key lies in growing back the old forest. That is exactly what this bird needed. Unlike in other cases of extreme endangerment, like Hawaii, the ivory bill is a case in which the natural habitat of the bird is getting progressively better. And I would add that even if the ivory bill fails, we should accelerate the process.”

The fuzzy images of the ivory-billed woodpecker have convinced many scientists of the bird’s existence. But doubters remain, says Cornell University’s John W. Fitzpatrick: “As we anticipated, there isn’t universal acceptance of the video as conclusive hard evidence. The video is blurry, and there are people who dispute our interpretation of the video.”

To respond to the skeptics, Fitzpatrick and his colleagues plan to make more evidence available over the next few months. “We have a lot of unpublished data from last year: signifi cant numbers of acoustic signals that do give us hope that there are birds in several places,” he says. “But it is all uncertain because the acoustic analysis will never leave us sure unless the bird is yakking right into our microphone.” The team will also keep scouring the woods, Fitzpatrick adds, “until we get a beautiful photo.”

NOT SO PROOF-POSITIVE?

IVORY-BILLED WOODPECKER, last seen in the 1940s, appears to be alive in the forests of Arkansas. This 1935 photograph has been colorized.

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